Gear ratios - 2007 Fit vs 1996 Civic

[PaleMelanesian]

The Fit has been widely criticized as being geared too low. The result being it runs at high rpm at highway speed. Sometimes called a "buzz-bomb".

2007 Honda Fit
5th gear - 0.757
Final drive - 4.294

Then I looked up my 1996 Civic.
5th gear - 0.700
Final drive - 4.25

So this means I'm driving a buzz-bomb as well! The Fit's 1.5 engine has almost identical output to my 1.6 non-vtec, both in peak numbers / rpm and when comparing the dyno charts. They're also rated for the same mileage: 33 / 38.

It's not usually an issue for my normal driving - my routes are 55mph max. But on the interstate, where 70mph = 3200 rpm, HS-P&G becomes the only option for good mileage.

[shifty35]

3k RPM is the Civic's favorite rpm for steady state FE.

The Fit has a shorter 5th gear and a shorter final makes the overall shorter than yours.

Fit: 55 mph = 2784 RPM, 70 mph = 3408 RPM
Civic DX: 55 mph = 2578 RPM, 70 mph = 3243 RPM

You're going roughly 5 mph faster at the same RPM.

I wouldn't call the DX transmission a buzz bomb at all. Try the CX/VX transmission, which is roughly the same as the Insight's...

Granted, I tossed the DX trans in my old Civic for an EX one... now *that* is a buzz bomb.

Don't even get me started on the DOHC B16 / 99-00 Civic SI 5th and final! Something like 4.5-4.7k rpm at 60 mph...

[PaleMelanesian]

Ha! You're right. For the 96-00 series, I've probably got one of the best transmissions.

But why do they do this? If you want to run 4.5k rpm on the highway, you can always use 4th gear, right?!!!

[xcel]

Hi Andrew:

___Your DX might even be worse The calc’s to find RPM at 60 include the diameter of the tires. The Fit w/ a stick uses 175/65/R15’s with a diameter of 23.0” (Circumference of 6.0214 ft.) and an RPM at 60 mph of 2,850

___The formula for R’s at a given mph as follows: [(mph) * (fifth gear ratio) * (final drive ratio) * (88)]/(tire circumference)

___Others of note …

07 Corolla w/ a stick: 2,305
07 Yaris w/ a stick: 2,660
08 Smart ForTwo: 2,857

___Good Luck

___Wayne

[PaleMelanesian]

Oooooh! Didn't think of that. I have 175/70/13's.

That 3200 at 70 is my observed actual rpm. Calc'd by your formula is 3093. About the difference I've observed between speedo / odo and reality.

[xcel]

Hi Andrew:

___You drive less of a buzz bomb than the current generation Fit …

My spread sheet pulled a 2,654 RPM at 60 mph for your DX w/ a stick:

Tire diameter of 22.6” (circumference of 5.91’) - 60 mph - fifth gear ratio of .700 - final drive of 4.25 yields 2,654 RPM.

___Good Luck

___Wayne

[PaleMelanesian]

That sounds about right. The point here is that Honda's ridiculous gear ratios is not a new problem.

It's not a terrible problem for me, given that I don't drive that fast. It also means that if I was to acquire a Fit, it would work for me in a similar way to what my civic does.

[-mr. bill]

The point is "Honda's ridiculous gear ratios" has nothing to do with 0-60 times or quarter miles. Unless somebody thinks that a 1996 Civic DX was "tuned" by HoA for street racing.

-mr. bill

[xcel]

Hi Mr. Bill:

___I sure wish I knew what it had to do with? Pulling a 1,000 # trailer at 60 mph possibly? Honda’s choice to run their smallest cars with relatively higher powered engines did not make any sense 3 years ago and it most certainly doesn’t make any sense today?

___Good Luck

___Wayne

[ksstathead]

Just bought a 2008 Honda Fit with the 5AT for my wife. First trip out, 2 hours at 70mph cruise control was 35.2 mpg (new EPA 27/33). Return trip no cruise control with 9 mph head wind was 35.5 mpg (speed high 60's average with a little DWL). I was fairly pleased with that. Edit: 452 ft elevation change, downhill with cruise, uphill on return trip.

But the 5AT's RPM at 70 mph ran 2585 to 2615 almost all the time, and quiet as a mouse. This is substantially lower RPM than my Tacoma or CRV, I think.

So, is the MT geared lower than the AT?

I like the 5 speed auto. It can be flat towed and it goes into fuel cut on most every decel in gear. Has paddle shifters which I hope can help reduce RPM in town by bumping up early. Also, I can induce fuel cut and save brake wear by decel with the tranny when I cannot coast or am coming in hot to a stop.